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$3.00 Simple Biochemistry Quiz on Hemoglobin
- From Chemistry: Biochemistry
- Closed, but you can still post tutorials
- Due on Sep. 07, 2008
- Asked on Sep. 06, 2008 at 09:07:22AM
Q:1.
In the binding of oxygen to hemoglobin, the relationship between the concentration of oxygen and the fraction of binding sites can be best described as:
a. hyperbolic
b. linear with a negative slope
c. random
d. linear with a positive slope
e. sigmoidal
2.
In hemoglobin, the transition from T to R state is triggered by:
a. subunit association
b. proton binding
c. heme binding
d. subunit dissociation
e. oxygen binding
3.
Which of the following are structural features of myoglobin?
a. the heme group is bound on the surface of the protein
b. myoglobin is mainly composed of strands
c. all of the other choices are true
d. the protein has quaternary structure
e. the iron atom is coplanar with the porphyrin ring in oxymyoglobin
4.
As oxygen binds to Hb subunits:
a. the O2 displaces His F8 releasing the F-helix to change conformation
b. a distal Asp forms a hydrogen bond with the bound O2
c. the His F8 dissociates from heme iron coordination
d. the heme iron atom moves back into the plane of the porphyrin, triggering a conformational change in the F-helix and the at alpha-beta subunit interface.
e. the heme iron is pushed out of the porphyrin plane and thus distorts the entire subunit
5.
Which of the following is TRUE concerning 2,3-bisphosphoglycerate (2,3-BPG)?
a. it is normally found associated with the hemoglobin molecules that are extracted from red blood cells
b. all of the other choices are correct
c. it binds at a distance from the heme groups of hemoglobin
d. it decreases the affinity of hemoglobin for oxygen by stabilizing the T-state
e. it binds with lower affinity to fetal hemoglobin than to adult hemoglobin
